<p>分值题</p>
<div *ngIf="!editable">
  <p>{{question.title}}</p>
  <p class="range-field">
    <label>分值： {{question.answer}}</label>
    <input type="range" [(ngModel)]="question.answer" min="0" max="10">
  </p>
</div>
<div *ngIf="editable && isEditing">

</div>
<div *ngIf="editable && !isEditing">
  <p>{{question.title}}</p>
  <p class="range-field">
    <label>分值： {{question.answer}}</label>
    <input type="range" value="50" min="0" max="10" disabled>
  </p>
  <div class="btns">
    <button (click)="onEdit()" class="btn">编辑</button>
    <button (click)="onDelete()" class="btn">删除</button>
  </div>
</div>